1. Field of the Invention
The present invention relates to heat sink clips, and particularly to a clip which readily and securely attaches a heat sink to an electronic device mounted on a circuit board.
2. Prior Art
Computer electronic devices such as central processing units (CPUs) frequently generate large amounts of heat. Many modern high frequency and high speed CPUs become particularly hot during operation, which can destabilize operation and cause damage. A heat sink placed in thermal contact with an electronic device mounted on a socket transfers heat from the electronic device through conduction. Oftentimes, the heat sink is secured to the electronic device by a clip.
Referring to FIG. 6, a conventional clip assembly comprises a pin 1 and a plug 2. The pin 1 includes a columnar body 3 having a screw thread, and a bifurcated barb 6 formed at a bottom end of the body 3. An aperture 4 is defined through an upper portion of the body 3, and a vertical slot 5 is defined through a lower portion of the body 3 in communication with the aperture 4. The plug 2 includes a shaft 7 corresponding to the aperture 4 of the pin 1, an expanded head 8 formed at a top end of the shaft 7, and a cone-shape insertion end 9 formed at a bottom end of the shaft 7. The insertion end 9 has a diameter substantially greater than that of the shaft 7.
In assembly, the pin 1 is successively extended through a corresponding aperture 12 of a heat sink 10 and a corresponding fixing hole 22 of a circuit board 20. The plug 2 is then plugged into the pin 1, with the insertion end 9 of the plug 2 pushing along through the vertical slot 5 of the pin 1. The insertion end 9 of the plug 2 then clasps the barb 6 of the pin 1, thereby fixing the heat sink 10 to both the circuit board 20 and an electronic device 24 mounted on the circuit board 20.
The conventional clip assembly is generally made of insulative material and not attached to a grounding circuit of the circuit board 20. Therefore, the clip assembly does not provide electromagnetic interference (EMI) shielding for the electronic device 24. This can compromise the soundness and stability of the electronic device 24. On the other hand, U.S. Pat. No. 6,112,378 discloses some approach. Anyhow, an easy and economic design is still desired.